Magnetic door catch



2 Sheets-Sheet 1 m & Bi A/ AV/P w INVENTOR. I 0. feezbr M- O. TEETOR MAGNETIC DOOR CATCH Nov. 2, 1954 Filed March 1'7, 1951 Nov. 2, 1954 Filed March 17. 1951 M. O. TEETOR MAGNETIC DOOR CATCH 26 J7 W z 2 Sheets-Sheet 2 M 0 I%I;ENTOR.

,959 e825? JM Q W "77* United States Patent MAGNETIC DOOR CATCH Macy 0. Teetor, New Orleans, La. Application March 17, 1951, Serial No. 216,117 7 Claims. (Cl. 292-2515) This invention relates. to a or other closure member in attraction.

It. is common experience with cabinetware that considerable difiiculty is often encountered with the operationof the cabinet latch or. catch because of warpage, sagging, or other misalignment of portions. of the cabinet either during or after the initial installation. In the usual type of cabinet catch, one of the catch elements is fastened to the door and the companion catch element is mounted in coacting position. on the cabinet frame or shelf. Consequently, evena slight degree of change in the relative positions of the cabinet frame. and. door will result in improper contact between. the catch elements which can usually be corrected only by removing one or both catch. elements and remounting them in properly aligned positions.

In my prior U. S. Patent No. 2,508,305 issued May 16, 1950, I have described and claimed a magnetic door catch which overcomes the above mentioned objections ordinarily encountered incabinet catches. The magnetic catch comprises a pair of cooperating magnetand armature elements adapted to be mounted inv self-adjusting coacting positions on a door and its adjacent frame structure. On of the catch elementsis rigidly mountedon its supporting member and the other catch elementv is resiliently and loosely mounted for outward movement toward the rigidly supported catch element when. the door is in closed. position. Simultaneously with. such outward movement, the movable catch element mayalso undergo limited angular or rocking movement. topermit automatic full surface engagement between the contact faces of the catch elements even though there may be relative misalignment between the door and frame structure.

The present'invention relates to a novelmagnetic catch having. a substantially simplified. and moreeconomical construction as compared with the device. shown in my prior patent but which also possesses. the same general advantages and operating characteristics asthe previously patented device. As will hereinafter appear, the magnetic catch comprising the present invention is. particularly suited for installation in the factory or as part of the original cabinet construction, but it is also capable ofbeing utilized by home owners and others as replacement hardware to substitute for other types of catches on preexisting cabinetware.

'A primary object of" the present invention is to provide a novel magnetic catch characterized by simplicity of construction and operation and which is relatively inexpensive to manufacture.

A further object of the invention is to provide a novel magnetic catch consisting of relatively few parts whfireiby the catch may be easily assembled and. insta e Another object of the invention is to provide a.novel simplified form of magnetic catch for cabinetware or the like which lends itself readily to built-in installation as part of the original cabinet construction.

Still another object of'the invention is to provide a novel magnetic door catch for cabinetware or the like which is simple in' construction and operation and which functions effectively even though the portions of the cabinet structure which support the catch elements be come misaligned relative to each other through warpage, sagging, or other causes.

Other objects and advantages of the invention will device for retaining a door closed. position by magnetic elsewhere.

2,693,382 Patented Nov. 2, 1954 become apparent from the subsequent detailed description of the invention taken in connection with the accompanying drawings, wherein:

Fig. 1 is a front elevational view, on a reduced scale, of a cabinet provided with a. magnetic door catch comprising one embodiment of the invention and showing the relative locations of the various cooperating parts of the device;

Fig. 2 is a front elevational view, on an enlarged i cale,1 of a portion of the cabinet frame illustrated in Fig. 3 is a vertical. sectional view taken along the line 3-3 of Fig. 2 and showing the position of one of the catch elements when the cabinet door is open;

Fig. 4 is a view similar to Fig. 3 butwith' the cabinet door in closed position;

Fig. 5 is a perspective viewof the magnet element of the device;

Fig. 6 is a horizontal: sectional view showing the manner in which one of the catch elements adjusts itself automatically to permit effective full face contact with the other catch element in spite of relative misalignment of the cabinet door and frame structure;

Fig. 7 is a' horizontal sectional view showing a modi fied form of the inventionwith thecabinet door in open position; and

Fig. 8 is a view similar to. Fig. 7 but with the cabinet door in closed position.

Referring first to Fig. l of the drawings, a wooden cabinet is shown comprising a door 11 hingedly secured to a cabinet frame 12. The cabinet is provided with a magnetic door catch embodyingthefeatures of my inventionandconsisting of a magnet unit 13 mounted adjacent the upper right-hand corner of the cabinet frame 12' and a cooperating armature unit 14 secured in a corresponding locationat the innerface of the-door 11. It will be understood: that the magnet unit- 13 and the armatureunit 14 are thus mounted in coacting positions on the cabinet frame and door, respectively, so that the. armature unit 14' engages the magnet unit 13 when the door 11- is in closed position adjacent the cabinet frame 12.v For purposes hereinafter described,

theouter edge of the cabinetframe 12 is also provided with a pair of. bumpers. or spacing. members in the form of v circular rubber pads 16 secured to the cabinet frame adjacent the upper and lower corners thereof Although two such bumpers 16 are shownin-Figr 1, it will be understood that the number of bumpers maybe altered to fit the circumstances of each installation and that the bumpers may also be mounted on the door 11 instead ofon the frame 12.

Although as shown in the drawingthe magnet unit 13 is secured to the cabinet frame. and the armature unit 14 is secured to the door, it will be understood that the two units may be mounted in reverse locations if desired. Also, the magnetand armature units need not necessarily be mountedin the exact positions on the cabinet structure illustrated in Fig. 1. For example, the catch elements maybepositioned adjacent the bottom or central portions of the cabinet structure if desired.

Referring to Figs. 2 to 6 inclusive. the magnet unit 13 is shown by Wayof illustration as comprising a cylindrical cup-shaped permanent magnet element. indicated generally at 17, which is loosely disposed inan enlarged concentric hole or recess 18 in the cabinet frame 12 and extending inwardly from the outermost face thereof. As a result of this arrangement, I am able to eliminate the use of a separate or independent magnet housing inasmuch asthe recess 18 in'the cabinet frame 12 constitutes in effect an: integral or built-in housing structure for the magnet. The magnet element 17 is provided with an axial aperture or bore 19 at the inner end thereof and an axial counterbore 21 extending to the opposite. or outer end of the magnet unit whereby to provide an enlarged recess or cavity therein. The magnet 17 is formed from a suitable magnetic metal or alloy and I prefer to employ the alloy known commercially as Alnico which comprises essentially aluminum, nickel. and cobalt. The magnet 17 is preferably so magnetized that regions or areas of opposite polarity are provided at the outermost flat annular contact face of the magnet, indicated at 22.

As will readily be seen from Figs. 2 to 6, the outer diameter of the magnet 17 is slightly less than the diameter of the recess 18 in the cabinet frame 12 whereby to provide an annular clearance or space 23 between the magnet and its recess. As described hereinafter, the provision of the annular clearance 23 permits the magnet 17 to assume a cocked or angular position within the recess 18 thereby imparting automatic self-adjustability during operation of the catch.

For retaining the magnet element 17 within the recess 18, a screw 24 extends through the aperture 19 into the cabinet frame 12 at the base of the recess 18 with the head portion, indicated at 26, of the screw being disposed in the cavity formed by the counterbore 21. The diameter of the screw 24 is substantially less than the diameter of the aperture 19 in order to permit a limited degree of angular or cocking movement of the magnet 17 relative to the screw 24. A helical spring 27 is disposed around the screw 24 with its opposite ends in coacting engagement with the screw head 26 and with the shoulder, indicated at 28, formed between the bore 19 and the counterbore 21. As seen in Fig. 3, the spring 27 by its resilient action normally urges the magnet element 17 inwardly of the recess 18 and when the door 11 is in open position the magnet 17 is thereby retained in its retracted position with the inner end thereof abutting the base of the recess 13. In such retracted position, it will be seen from Fig. 3 that the annular contact face 22 of the magnet is recessed to only a very slight degree from the outer face of the cabinet frame 12 and is, therefore, in substantially flush relation therewith.

The armature unit 14 comprises a flat centrally apertured circular washer 29 formed from a magnetic metal such as iron and steel and having a diameter substantially coextensive with the diameter of the magnet 17. The washer 29 is secured to the inner face of the door 11 by means of a screw 31 having its head portion countersunk within the washer 29 whereby to present a flat contact surface for full face engagement with the ma net 17. It will be understood that the force resultin from the magnetic attraction between the magn 17 and e Weshe 29 is "r tha th tension exerted by the spring 27 thus permitting outward movement f the magnet 17 into en agement with the washer 29 when the door 11 is closed. However, when the door 11 is in open positi n the spring 27 forces the ma net 17 into i s inwardly retracted position in the recess 18 as described above.

In Fig. 4 I have illustrated the relative positions of the catch elements when the d or 11 is in closed position. When the door 11 is fullv closed, it will be seen th t the rubber bumpers 16 function to maintain a prede ermined. s acing of the door and frame members in.

order to insure proper operation of the catch. The hickness of the bumper 16 as shown in Fig. 4, is sufiicient so that when the d or 11 is fully closed in abutment wi h the bumpers 16, the magnet unit 17 must move outwardly against the tension of the spring 27 in order to en a e the washer 29. Thus, as the cabinet door 11 approaches closed position when being moved at a normal rate of closure, the magnet 17 moves outwardlyfrom the recess 18 into enga ement with the washer 29 and such engagement normally occurs an instant before the door 11 reaches its fully closed position. Thereaftenthe final closure and retention of the door in closed position is accomplished solely by the action of the spring 27 which is then under compression (Fig. 4). By means of this arrangement, it will be seen that the magnet 17 merely adheres to or establishes firm contact with the door but the actual retention of the door in closed position is accomplished through the resilient action of the spring 27. In this manner, proper functioning of the magnetic catch is realized and undesirable looseness or rattling of the closed door is completely avoided. When the door 11 is opened, the spring 27 is fully compressed or collapsed by movement of the shoulder 28 toward the screw head 26 and the collapsed spring thereby serves as a rigid breaker for completely disrupting the magnetic bond between the magnet 17 and the washer 29.

The provision of the bumpers 16 in the manner just described also serves another important purpose, nameorder to obtain satisfactory operation.

ly, the protection of the magnet 17 against direct impact with the armature comprising the washer 29. Magnetic alloys are in most cases quite brittle and low in impact resistance, and as a result of these properties it is important to avoid direct impact between the magnet and armature elements such as might occur during forceful slamming of the door to closed position. Although the annular contact face 22 of the magnet 17 is substantially flush with the outer face of the cab inet frame 12 when the magnet is in its normal retracted position, it will be seen from Fig. 4 that even when the door 11 is slammed with severe force, the washer 29 cannot possibly engage the magnet 17 with a slamming impact because of the presence of the bumper 16. Thus, the bumpers 16 absorb or receive the slamming impact and the spacing effect of the bumpers 16 is such that the magnet 17 must always move outwardly against the action of the spring 27 in order to effect magnetic engagement with the armature element.

As hereinbefore mentioned, an important feature of the present invention resides in the self-adjustability of the catch elements to permit effective full face contact between the magnet and its armature even though the cabinet door and its adjacent frame structure may occupy misaligned non-parallel positions as a result of warpage, sagging, or other causes. This feature is illustrated in Fig. 6 wherein the door 11 is shown in nonparallel misaligned position relative to the frame 12. Because of the fact that the magnet 17 is loosely and resiliently mounted within the recess 13, angular or twisting movement of the magnet 17 occurs within the limits of the annular clearance 23 between the magnet and its recess 18 and also the annular clearance between the screw 24 and the aperture 19 at the base of the magnet. As a result of such angular or cocking movement of the magnet, as seen in Pig. 6, full face flatwise engagement between the washer 29 and the annular contact face 22 of the magnet is realized. In Fig. 6 the misalignment between the door and frame structure is illustrated in a horizontal plane, but it will be quite apparent that the structure of the catch is such that even if the cabinet door and frame are misaligned in a vertical plane, suitable angular or cocking movement of the magnet 17 can also occur in a vertical plane. Hence, the magnetic forces in my device are utilized to their fullest extent at all times with the self-adjustability of the movably mounted catch element compensating for all types of misalignment between the door and frame.

Another important advantage of the simplified mag-- netic catch constituting the present invention resides in the fact that it is unnecessary to have absolute centerlng or alignment between the catch elements per se in In the usual type of mechanical or frictional door catch, satisfactory operation is obtained only when the catch elements are mounted for perfect coacting engagement with each other. If one of the elements of a mechanical or frictional catch is slightly off-center or misaligned relative to the other catch element, then either the catch does not operate at all or else the door can be opened or closed only with difiiculty. Such misadjustment of the catch elements can occur as a result of changes in therelative positions of the supportmg door and frame structures after the catch has been installed or may be the result of inexact original installation of the catch elements even when the door and frame members are in precise alignment. it will be seen from Fig. 4 that even if the washer 29 is displaced upwardly or downwardly or toone side relative to the magnet 17 so that the two elements are not in concentric relation, nevertheless, within appreci-- able limits the misalignment between the catch elements will not materially affect the operation of the catch. As explained above, the purpose of the magnetic contact between the catch elements is merely to cause the door 11 to adhere to the movable magnet element and it is the action of the spring 27 which serves to retain the door in closed position. Thus, as long as there is a substantial degree of magnetic contact between the mag net and armature elements, the catch will function satisfactorily even though the elements are not concentrically aligned at their contact faces.

In Figs. 7 and 8, I have shown a modified form of the invention in which the spacers or bumpers 16 are With the present magnetic catch,

eli nisatedzser-that;the-: candireetly:ergsasesvthe"cabin t fra an 'lla' xlmdrpml lnthisa inbedwient'ot heet; ,tur aand: assembly of heimasn e -24i an he pring; '21; re; hesame-a in ubediferm' f he in ntion However, hereeessiv ind ated: at 32,;tcr the.-.masn t. 17. is of substantially gr at r; depth} than: in; the; first form. f he: WWlfiQBgSO 411st; wh m he magnet is. inits1n0rrna1 retrac ed-po ion.- (Fig.--.7)i the annular-contact face .22. 0t t -magnet s reeessed inwardly aasub tantial exten from: the, front; ace; of he cabine fr me 12, The mature el me t omprising; a; washer 3.3 ext nds into he rec 2 for cnt ctinsy he m gn t: 17 when; the door, 11 s. n: 19se .1 Posi ion; abutti he; frame. 12-. However, the depthct: he. rece s: 321th. suflici ntly greater,thanthe-correspon i lg" imm 17 so that even when the door 11 is' l laclosedposition in contact with the frame 12 (Fig. 8), the magnet 17 must move outwardly against the force ofthe spring 27 in order: to contact 'the armature element. Washer 33 swfz mal ie nd ameterl than' th magnet 17 so that the washer can still extendinto the recess 32 even-though the washer 33 may notbealigned inexact concentric relation with the recess .32.; Thus, in,the modified form of my invention, the spacing and protective functions ofthe bumper-16' are fulfilled. by thei'ucreased depth. of the hole 32-and the normally recessed .relationof' the magnet-17 therein.- It will be seen that because of the greaterv depth ,of the hole 32, the magnet 17 is fully recessedwithin the hole 32 at all times duringopen or closed positions ,ofith e door 11. During pen n i f the o r, t emasnet '17 may move -.o t ar y from the osition shown in- Fig.8, until thespring 27 is fully col apsed and the magnetic bond is broken whereupon the magnet 17 is then retracted to its Fig. 7 position by the action of the spring 27 as in the first embodiment of the invention.

From the foregoing description, it will be seen that my present invention provides a simplified form of magnetic catch which is relatively inexpensive to manufacture and which may be readily assembled and installed. The catch has a minimum of separate parts and does not require the provision of an independent housing or casing for the movably mounted catch element. Instead, a suitable bore or recess is provided in the supporting cabinet structure to serve as a housing for the movable catch element. Because of the necessity of providing the enlarged bore or recess in the cabinet frame or door to receive the movable catch element, it will be seen that the present invention is best suited for initial installation, e. g. in the factory, as part of the original cabinet construction. However, under many circumstances, the catch can also be employed by the ordinary home owner or craftsman provided suitable precautions are taken to obtain the proper depth and diameter for the recess in the cabinet structure which receives the movable catch element.

Although the invention has been described in detail herein in connection with certain specific embodiments, it will be understood that various modifications and equivalent structures may be resorted to without departing from the scope of the invention as defined in the appended claims.

I claim:

1. A magnetic catch for holding a closure member in closed position adjacent a frame member and including a pair of cooperating armature and permanent magnet units adapted to be mounted in coacting positions on said members, one of said units being adapted to be rigidly afiixed to one of said members and the other of said units comprising a generally cup-shaped element having a base portion at one end and an annular contact face at its opposite end, said element being adapted to be movably disposed within a complementary inwardly extending recess in the other of said members, retaining means adapted to extend loosely through the base portion of said element into said other member at the base of said recess for retaining said element in position in said recess, and spring means coacting with said retaining means and the base portion of the movable element for normally urging the latter inwardly of said recess but permitting outward movement thereof against the action of said spring means for effecting magnetic The 6 contact said one unit. and annular: ontact face. off and 1 elemen Atmaznetiecatchfor. holding a: closure member; in closed position adjacent aframe member,- said: catch comnrising. a flat annular armature element adapted. to be-rigidly seeured-to-one of=said1members-, a generally cylindrical cup-shaped. permanent magnet element havingan annular ontactxfaee at one. end. andabaseportion at; its; pposi e end. provided. with an axial aperture heretlurcugh, said magnet. element being vadapted tube movably/disposed; with-in a complementary inwardly. ex, tending, recess in i the. other of said. members, elongated retaining, means-adapted; to extend loosely. through said per ure. n-thebas p rtioniotsaid magnet elementdnto said other member at the base of said recess for re.- aininesaid masnet lement in PQ i I 'iIL i recess, and; spring, means-coaching with said retaining means and the, base; portion, of,- said: magnet: element for nor.- mallyursinsthe lat er. inwardly of a said, recess but per? mitting ou ward movem nt ofsaidmagnet-elementagainst thevv i n of. said; spring: means for ffecting. m gnet Contact of; saidannular contact face; with said armature eleme 3. A I magne tehfcr hol g. a: closure. member in closed p sitionadjacent. a frame. memb r, said: atch omprising an armatur lement a apt d. o be. rigidly ecure o. one-oil aid'me ers, ylindricalmasnet element; adapted tobe-receivedaxially within a com l me tary inwardly extendins recess inzthe Q h r f said members,- said ma net element. havingtan axial cavity adjacent its outerend and an axial aperture,- at itsflinner end, an elongated retainer adapted toextend; throughsaid aperture; in es aidl t er member. at; the base of said recess and having a head portion disposed in said cavity, and spring means disposed in said cavity in coacting relation with the head portion of said retainer and with said magnet element for normally urging the latter inwardly of said recess but permitting outward movement thereof against the action of said spring means for effecting magnetic contact of said magnet element with said armature element, said recess being of greater diameter than said magnet element and said aperture being of greater diameter than said retainer whereby to provide annular clearances therebetween for permitting said magnet element to undergo limited angular movement simultaneously with said outward movement, said angular movement thereby facilitating full face flatwise contact between said magnet and armature elements even when said closure and frame members occupy non-parallel misaligned positions.

4. A magnetic catch for holding a closure member in closed position adjacent a frame member, said catch comprising an armature element adapted to be secured to one of said members, a cylindrical magnet element adapted to be movably mounted in an inwardly extending recess in the other of said members, said magnet element having an axial bore at one end and an axial counterbore providing an enlarged cavity at the opposite end of the magnet element with a shoulder portion at the juncture of said bore and said counterbore, a screw adapted to extend through said bore into said other mem ber at the base of said recess and having a head portion disposed in said cavity for retaining said magnet element within said recess, and a helical spring in said cavity disposed around said screw in coacting engagement with said head portion and with said shoulder for normally urging said magnet element inwardly of said recess but permitting resilient outward movement thereof against the action of said spring into magnetic contact with said armature element.

5. A magnetic catch for holding a closure member in closed position adjacent a frame member, said catch comprising an armature element adapted to be secured to one of said members, a cylindrical magnet element adapted to be movably mounted in an inwardly extending recess in the other of said members, said magnet element having an axial bore at one end and an axial counterbore providing an enlarged cavity at the opposite end of the magnet element with a shoulder portion at the juncture of said bore and said counterbore, a screw adapted to extend through said bore into said other member at the base of said recess and having a head portion disposed in said cavity for retaining said magnet element within said recess, and a helical spring in said cavity disposed around said screw in coacting engagement with said head portion and with said shoulder for normally urging said magnet element inwardly of said recess but permitting resilient outward movement thereof against the action of said spring into magnetic contact with said armature element, said recess being of greater diameter than said magnet element and said bore being of greater diameter than said screw whereby to provide annular clearances therebetween for permitting said magnet element to undergo limited angular movement simultaneously with said outward movement, said angular movement thereby facilitating full face fiatwise contact between said magnet and armature elements even when said closure and frame members occupy non-parallel misaligned positions.

6. In a magnetic catch having a pair of cooperating magnet and armature elements adapted to be mounted on supporting door and frame members with one of said elements being movable under magnetic attraction toward the other of said elements, the combination of a supporting member having an inwardly extending recess, said one element being movably disposed in said recess, retaining means extending loosely through the movably mounted element into said supporting member at the base of said recess for retaining the movably mounted element within said recess but permitting limited sliding movement of the movably mounted element on said retaining means, and spring means coacting between said retaining means and the movably mounted element for normally urging the latter inwardly of said recess but permitting resilient outward movement thereof against the action of said spring means.

7. In a magnetic catch having a pair of cooperating magnet and armature elements adapted'to be mounted on supporting door and frame members with one of said elements being movable under magnetic attraction toward the other of said elements, the combination of a supporting member having an inwardly extending recess, a generally cup-shaped element having a base portion at one end and an annular contact face at its opposite end, said cup-shaped element being movably'disposed in said recess, retaining means extending loosely through the base portion of said cup-shaped element into said supporting member at the base of said recess for retaining said cup-shaped element in position in said recess, and spring means coacting with said retaining means and the base portion of the cup-shaped element for normally urging the latter inwardly of said recess but permitting resilient outward movement thereof against the action of said spring means.

References Cited in the file of this patent UNITED STATES PATENTS Number Name 7 Date 2,203,580 Ronning June 4, 1940 2,240,035 Catherall Apr. 29, 1941 2,508,305 Teetor May 16, 1950 2,521,885 Vasquez Sept. 12, 1950 2,524,924 Pampallona Oct. 10, 1950 FOREIGN PATENTS Number Country Date 544,110 Great Britain Mar. 27, 1942 629,903 Great Britain Sept. 30, 1949 

